Kind of related, but I've had a lot of trouble with the P3 paints becoming unmixed, especially the metals. The first time I got the metals it took about an hour of shaking, no joke, for the color to mix with the metal flakes. I truly did not think they were going to mix at all but kept shaking throughout the day out of frustration. If they sit for a day they have to be shaken for another 5-10 minutes the next time I use them. If they sit for a month I will come back to see the platinum has turned into a layer of metal flakes, a layer of yellow, and a layer of green that now need to be shaken extremely vigorously. The same paint can come out various shades depending on how long it's been shaken and it never mixes completely.
There were some Privateer minis I was interested in, but between this thread and my experiences with the paint, I'm going to skip them.